Christ the King's Omar Calhoun signed his NLI to UConn Wednesday.Joseph Staszewski

It was a single act that speaks volumes about Omar Calhoun.

The Christ the King senior guard was taking his SAT exam at Bishop Ford on Oct. 1 when a handicapped student needed to use the restroom afterward. Calhoun volunteered to help. He escorted her there, held her bag and even walked her to the lobby.

“I didn’t think nothing of it,” he said. “That’s just the type of person I was brought up to be. I just helped her out.”

The humble Calhoun told no one of what he’d done, but exam proctor Joseph Mingrone wrote a letter to Christ the King Principal Peter Mannarino praising Calhoun, calling him a credit to the school and his family.

Royals athletic director Bob Mackey read the letter before The Post’s reigning All-City Player of the Year signed his National Letter of Intent to UConn at the school Wednesday night. His father Omar Calhoun Sr. said he was fighting back tears.

“I was impressed that someone would recognize that part of him, that he is not just a great basketball player, he’s a great person too,” Omar Sr. said. “That’s what the University of Connecticut is getting and wants him to be.”

Being a leader is something Calhoun prides himself on doing on and off the court for the Royals, an attribute CK coach Joe Arbitello credits to his upbringing. He hopes it rubs off on the younger members of the program.

“He carries himself in a different way,” Arbitello said. “He doesn’t think he deserves anything. When I read that letter, I wasn’t surprised at all.”

The 6-foot-5 Calhoun’s driven and hard-working nature has turned him into one of the nation’s prospects. He is the 10th-ranked shooting guard in the nation by Scout.com and led the CHSAA Class AA in scoring at 21 points per game last season.

The Brooklyn native was a key cog in the Middle Village school capturing the New York State Federation Class AA championship two years ago and last season he netted 33 points in an overtime loss to Mount Vernon in the Federation final. He became just the second CK player to reach the 1,000-point mark as a junior since Khalid Reeves and is around 600 points behind him for the top spot on the school’s all-time leading scorers list.

“Tomorrow I’m going to be right back in the gym, making sure I am as sharp as possible for this year and coming in next year at UConn,” he said.

Calhoun did take a moment to step back and reflect on his accomplishment and enjoyed sharing it with the Christ the King basketball family. They will miss him just as much.

“It’s like you are losing someone from your family,” Arbitello said. “I’ve been with him every day for four years.”

He believes Calhoun is primed for a big season just by watching the way he has handled himself in early practices. But he knows his success reaches far beyond what he does as a player, as evidenced by the letter from the Bishop Ford teacher.

“I just didn’t know anyone was writing anything to Christ the King,” Calhoun said. “That kind of surprised me, but it’s something I take honor in doing, carrying myself and great person off the court as well as on the court.”